Vented sector parachute



July 13, 1954 cl- 2,683,575

VENTED SECTOR PARACHUTE Filed Nov. '7, 1950 4 Sheets-Sheet l INVENTOR; #HMW' HE/A E/K BY a -14 July 13, 1954 H. G. HEINRICH 2,683,575

VENTED SECTOR PARACHUTE Filed Nov. 7. @950 4 Sheets-Sheet 2 BY ULLh w y 13, 1 H. G. HEINRICH 2,683,575

VENTED SECTOR PARACHUTE Filed Nov. '7, 1950 4 Sheets-Sheet 5 INVENTOR. Hid/1407' 6', 1404 05 July 13, 1954 HEINRICH 2,683,575

VENTED SECTOR PARACHUTE Filed Nov. 7, 1950 4 Sheets-Sheet 4 mmvrox. HEX/14076. HEM/4W6 Patented July 13, 1954 UNITED ST A'i'ENT ()FFICE VENTED SECTOR PARACHUTE Application November 7, 1950, Serial No. 194,546

31 Claims. (Cl. 244142) (Granted under Title 35, U. S. Code (1952),

see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to stable parachutes and more particularly to parachutes having comparatively low bulk, high drag and loW or soft opening shock.

There are many factors which make the conventional fabric parachutes undesirable for high speed release, among these being sudden opening following release and high shock loading, lack of stability and excessive oscillation during descent also the bulk of the conventional fabric chute is somewhat objectionable.

According to the invention, my improved parachute includes a canopy which is formed of sectors or segments that are alternately nonporous and porous. The porous sectors of the canopy may be from 10% to about 50% more porous than the adjacent nonporous sectors. The fabric material is preferably omitted from the so-called porous portions of the sectors or segments, thus providing venting openings or passages, reducing to a great extent the amount of fabric sheet material that would ordinarily be used in a conventional canopy of similar diameter. This elimination of material in my improved canopy reduces the cost of the chute and also effects a material reduction in the bulk of the canopy when the same is packed or worn. The air passing through the porous, or vent portions in the sectors causes a much greater air turbulence above the canopy than in the case of a solid sheet canopy and this air turbulence causes a slower descent rate than the descent rate of a nonporous sheet canopy having a similar amount of fabric material therein.

It has been found that a parachute constructed in accordance with the invention, with the elimination of about 30% to 50% of the material usually employed in conventional canopies of similar size, as represented by the porous portions, or the portions of the alternate sectors that have been omitted, has a satisfactory and safe rate of descent which is about equal to that of a conventional chute of the same diameter composed of solid full length fabric sectors.

In connection with my alternate vented sectors canopy parachute, I also contemplate the use of an extended skirt portion of the uide surface type in which the skirt is extended downwardly from the periphery in a sort of truncated conical section with portions of this downwardly extending conical section adjacent the lower edge cut away, or omitted, so as to form a plurality of venting passages or openings spaced equally, or in a predetermined manner, around the extended skirt below the periphery of the canopy, with guide surface portions located at each side of these vents.

Another form of my invention comprises a substantially hemispherical canopy having the usual shroud lines tapering inwardly and downwardly from the periphery of the canopy and incorporating downwardly extension strips, or fabric extensions, attached at the lower ends of alternate sectors or gores and extending downwardly between spaced pairs of the shroud lines and secured thereto, thus providing a plurality of air vent openings therebetween spaced around the skirt portion of the canopy in a predetermined manner. In this form of the invention these extensions may be added to the alternate or predetermined sectors of existing conventional parachutes so as to constitute extensions of the selected gores or segments. In all of these forms a considerable saving of the parachute sheet material is effected relative to the effective drag area, and therefore a decrease in the bulk, weight, and a decrease in the size of the chute when packed relative to a conventional canopy of the same drag area can be accomplished without materially effecting the rate of descent performance, but increasing the stability. The improved canopy opens more slowly than the conventional hemispherical and flat sheet types of chutes, has materially reduced opening shock and greatly improved stability, making the chute desirable for the release at the high speeds.

Other objects and advantages will appear from the following description, taken in connection with the accompanying drawings in which like reference characters refer to like parts in the several figures of the drawings.

Fig. 1 is a side elevation of an inflated guide surface type of parachute during descent, incorporating my invention;

Fig. 2 is a plan view of the parachute disclosed in Fig. 1 looking downwardly toward the top of the fully inflated canopy;

Fig. 3 is a fragmentary side view of an inflated canopy of the guide surface type having a slightly different form of sector or guide surface, in which the stabilizing guide surface portionis constructed without internal ribs or webs, utilizing the shape of the gores of the canopy to hold the guide surface portion in position and providing long and short radial segments with sector 3 shaped venting openings between the long segments;

Fig. 4 is an enlarged fragmentary vertical sectional view taken through the canopy shown in Fig. 3 the right hand portion of the canopy being shown in elevation;

Fig. 5 is a fragmentary top plan of the canopy shown in Figs. 3 and e, illustrating the location of the extra cross webs or bulkhead members between the adjoining gores extending across the inner ends of the short sectors to retard the escape of air from below the short gores, to maintain the peripheral guide surface portion fully inflated and extended;

Fig. 6 is a top plan view of an inflated canopy employing large triangular or sector shaped cutout portions which provide venting passages or openings in predetermined gores so that the direct air stream passing through the venting portions will cause an air turbulence distance above or behind the canopy, causing the canopy as a whole to have a higher specific drag, the cut-out sector portions producing a canopy having alternate radially disposed long and short sores or sectors having alternate relatively large and small fabric areas:

Fig. '7 is a somewhat diagrammatic top plan view of a rectangular form of inflated canopy employing a stabilizing peripheral portion or guide surface, in which the center portion of the canopy is provided with elongated rectangular parallel air vents formed by employing alternate long and short fabric sectors;

Fig. 8 is a side elevation of the canopy shown in Fig. 'i the right hand portion thereof being broken away and shown in section;

Fig. 9 is a further modified form illustrating an inflated canopy of the flat sheet type in which alternate long and short radial segments or sectors are provided with the shroud lines extending along their adjoining edges and secured to the opposite edge portions of the long segments which extend beyond the shorter sectors, providing means for retaining the end portions or extensions of the long sectors in place during descent, the spaces beyond the short segments, between the end portions of the long sectors, thereby providing a plurality of circumferentially spaced venting passages or openings located around the peripheral portion of the canopy, each venting opening being located between an adjacent pair of the long sectors;

Fig. 10 is an enlarged fragmentary side elevation of an inflated canopy in which the longer sectors are each formed with a special guide surface located in a plane below the ends of the short sectors to provide a plurality of guide surface members with venting openings therebetween. The long sectors being preferably formed by the addition of specially formed extension members which are attached to the alternate sectors of a conventional parachute having gores or sectors of equal length;

Fig. 11 is an enlarged fragmentary vertical sectional view through the canopy illustrated in Fig. 10, more clearly illustrating the shape of the extension or attachment members which form the long sectors, and the position of the vents below the short sectors and between the long sectors;

Fig. 12 is a somewhat diagrammatic, exploded plan showing the lower end portion of a conventional parachute gore or sector, and the general shape of the two elements or blanks forming 4 the guide surface extension which produces the long gore as shown in Figs. 10 and 11; and

Fig. 13 is an enlarged fragmentary side elevation of the peripheral or skirt portion of a para chute canopy, illustrating a further modified form of extension members as applied to the sectors of a conventional fabricated parachute canopy.

Referring more particularly to Figs. 1 and 2 of the drawings, the reference numeral I denotes a sectors parachute of the guide surface type having a fabric canopy 2 formed to provide a low camber dome shaped top portion 3 terminating in an inwardly and downwardly tapered skirt portion forming a guide surface. The shroud lines 5 extend in vertical planes passing through the junctures of the adjacent edges of the gores or sectors la and Eb of the chute, into the bottom opening of the skirt portion and then curving upwardly and inwardly in the conventional inverted catanary contour. Vertically and radially disposed fabric supporting ribs or webs 6 are provided, secured to the curved portions of the shroud lines 5 and extending outwardly therefrom to the adjoining radially extending edges of the sectors of the canopy, being secured thereto to provide the necessary supporting web members for the guide surface portion 4 extending between the shroud lines 5 and the top portion 3 of the canopy. If desired, the shroud lines 5 may each pass through the top 3 of the canopy at some point between the periphery and the apex and then extend across the top of the canopy, above rather than entirely below the fabric sheet.

The canopy 2 is preferably formed from an even number of adjoining radial sectors or gores, the inner end portion of every other or alternate sector Th is cut away or omitted at some point between the periphery and apex of the canopy to provide a segmental shaped opening 1 or vented sector with a solid fabric sector Id at each side thereof. The top portion 3 of the parachute canopy, is therefore composed of alternate long and short sectors or gores Ta and "lb which produce the radially extending sector shaped openings I which are spaced around the center of the canopy 2. It has been found that from about 30% to of the canopy fabric material usually employed in the fabrication of a conventional parachute canopy can be safely omitted to produce the sector shaped openings F, without materially affecting the drag, or increasing the descent rate to a dangerous degree, and at the same time improve the stability of the canopy during descent. The omission of this material in the fabrication of my improved canopy permits the parachute to be constructed more economically, and in addition reduces the bulk and weight of the parachute.

Air passing through sector shaped openings 1 in the top 3 of the canopy, as the chute descends, creates a turbulence in the air directly above the canopy which increases the parachutes drag characteristics and the increased venting area produces a softer or slower opening of the chute, especially when released at high velocities, thus reducing the opening shock and strain on the chute, and on articles, or personnel being lowered thereby.

The construction of the canopy shown in Figs. 3 to 5 is slightly modified from that illustrated in Figs. 1 and 2. Instead of the internal webs or ribs 6, as shown in Figs. 1 and 2, the shroud lines 5a pass over the exterior or top of the canopy between the valleys at the adjoining edges of the segments, and end closure members or webs 8 are provided for closing the peripheral part of each sector, forming inverted trough like inflated peripheral guide surface portions. The alternate fabric sectors 9 of this form of canopy are shorter than the intermediate segments It so as to provide sector shaped openings H extending radially, in circumferentially spaced relation, about the center of the canopy. The inner ends of the short segments 9 are preferably provided with fabric bulkheads or webs 48.

In Fig. 6 a hemispherical canopy is illustrated composed of alternate long sectors or segments l2 and short sectors I3. Shroud lines I4 extend across the top and apex vent Me of the canopy, between the adjoining edges or valleys of the segments !2 and :3 with the side edges of the inner portions of the long segments l2 secured to the shroud lines it, thus supporting the inner end portions of the longer segments H2 at the edges of the sector shaped openings 15. This figure of the drawing illustrates a conventional fiat sheet canopy in which long and short segments or gores i2 and [3 are provided so as to leave a plurality of venting sectors i5 which are radially disposed around the apex vent Ma for producing a high air turbulence or interference drag in a manner similar to the performance of the canopies shown in Figs. 1 to 5.

In a modified form of parachute illustrated in Fig. '7 the top of the canopy is indicated by the reference number It and is somewhat rectangular having shroud lines i6 extending in transverse directions across the top. A guide surface or peripheral stabilizing portion ll is provided which extends inwardly and downwardly, the segments or panels of the canopy being indicated at it and HM, the segments 28a being shorter provide the openings or air vents I9 between the ends thereof. As shown in Fig. 7 three vents H) are provided, disposed in spaced parallel relation, the openings l9 being located between the longer segments i8. Air passing through the adjacent spaced elongated parallel openings H9 in the top 15 produces a high turbulence in the air stream directly above the top of the canopy, increasing the drag to produce a rate of descent substantially equal to that of a solid top canopy having substantially the same amount of fabric there- In the modified embodiment illustrated in Fig. 9, the reference numeral 29 denotes an inflated canopy during descent, comprising a plurality of radial segments or sectors 2! and 22 having alternate long and short radial dimensions. The segments 2i and 22 are secured together along their adjacent edges 23 in the conventional manner. Shroud lines 25 extend from the apex of the canopy along each of the adjoining secured edges 23 of the segments 2| and 22. The side edges of the long segments 2i which extend beyond the shorter sectors 22 are secured to the shroud lines 2 providing a series of rectangular, or substantially rectangular shaped openings or air vents 25 around the periphery of the canopy which ar located between the ends of the longer segments 2!. The chute thus comprising a plurality of long and short radial sectors 21 and 22 with radially disposed vent openings 25 located in spaced relation around the center of the canopy between the long sectors 2 I. Air escaping through these vents 25 during descent also produces tur bulence, increasing drag and reducing the rate of descent of the chute to that about equal to or less than the rate of descent of a solid flat sheet canopy of about the same maximum diameter. The air escaping through the vents 25 spaced around the periphery of the canopy during descent stabilizes the canopy so that the same is non-oscillating, also when the same is released at high speed it opens comparatively slow and therefore excessive high opening shock and strain on the canopy and an attached load are eliminated.

The outer ends of the adjacent spaced longer segments or sectors 2 la may be secured together by connecting cord members Zia as shown in Fig. 9, extending transversely to the shroud lines 24, connected at their ends to the extreme ends of the long sectors 2| and extending across the lower ends of the vents 25 thus limiting outward movement of the lower ends of long segments 2| and reducing the amount of air escaping through the vents 25 when the parachute is first released. The venting area through the openings 25 initial 1y reduces the opening shock considerably below that of conventional chutes, making this form of chute satisfactory for high speed release and the spaced arrangement of the sector openings 25 around the periphery makes the chute very stable during descent and therefore non-oscillating, also the elimination of fabric material to provide the venting openings 25 reduces the amount of material required for the fabrication of the chute as compared to a conventional chute of similar diameter, its lower opening shock characteristics permitting the chute to be made of lighter material, thus providing a parachute which is less bulky and more economical to manufacture.

A conventional parachute may be converted to the type illustrated in Fig. 9 by providing somewhat rectangular shaped extensions Zlb, each having a width about equal to the width of a segment at its wide end and sewing these extensions 2lb to the ends of the panels as indidicated at 2 lc, and to the shroud lines 24.

In Figs. 10 to 12 a further modification of the form shown in Fig. 9 is illustrated. The parachute canopy is indicated by the reference numeral 2B, composed of alternate long and short radial segments 21 and 28 joined together at 29 along their adjacent edges. Shroud lines 30 extend across the top of the canopy along the adjoining edges of the segments 21 and 28 and downwardly at the opposite edges of the lower ends of the longer segments 27, extending downwardly beyond the lower ends of the shorter segments, forming extensions 21a, leaving air vent openings 3| therebetween to permit the restricted escape of air during the opening and descent of the canopy, producing a stabilizing function.

The lower ends of long sectors 21 each comprise one of the extensions or attachment elements 21a, fabricated separately and sewed at its top edge to one of the alternate sectors or panels of a conventional type of parachute originally having equal length segments. As best seen in Fig. 12 these extensions 27a are sewed or otherwise secured at 210 to the lower ends of the (alternate) panels 21b. Each extension 21a comprises a somewhat triangular shaped sheet fabric portion or blank 32 having straight upwardly converging side edges 33 which are secured to the adjacent shroud lines 38. The upper ends 34 of the portions 32 are sewed at 21a to the lower ends of the alternate sectors 2'"), making the sectors 21b longer than the sectors 28 located at each side thereof. A somewhat semi-elliptical shaped fabric sheet or blank 36 is sewed along its curved edge 31 to the inwardly curved portion 38 of the blank 32, producing an outwardly extending air pocket; best seen in Fig. 11, the semi-elliptical shaped portions 35 forming guide surfaces 36a, each having a sharp air foil shoulder at 38 which breaks the continuity of the flow of air passing upwardly along the guide surface 33a as the canopy descends. Upwardly and inwardly inclined curved surface 3519 leading from the shoulder 39 merges into the end of the panel or sector 21.

Conventional hemispherical parachutes normally having a relatively high opening shock at high velocities and being unstable during descent, oscillating sometimes violently, can be converted into parachutes having low opening shock, much slower opening characteristics and stabilizing characteristics which make them nonoscillating, making them ideal for high speed release by adding the guide surface air pocket or eX- tension members Zla to the alternate sectors thereof.

Fig. 13 discloses a somewhat similar arrangement to that shown in Fig. 12 with the exception that the extension members are modified slightly. They are fabricated from two blanks t8 and ii cut from fabric sheet material and sewed together as indicated at 42. The blank 40 is substantially rectangular, having a width about equal to the width of the panel or segment 43 to which it is sewed at its top edge, as indicated at 45. The attachment forms a substantially uniform continuation of the panel segment 43 when in place, rather than extending downwardly and outwardly like the blank 32 in Fig. 10. The blank 58 is also formed with an upwardly and arcua-tely cut out portion to receive the somewhat semi-elliptical portion of the blank 4! therein. When a parachute incorporating 1e extensions shown in Fig. 13 descends the blank elements 4! incline inwardly and downwardly, forming spaced guide surface elements, extending around the canopy below the skirt. The openings e between the extensions function in the same manner as the openings 3! in Fig. 1G, or the openings 25 in Fig. 9. The shroud lines 46 are secured along the opposite edges of the blank 40, as indicated at 41.

After a conventional parachute has been modified by adding the extensions to the alternate segments of the canopy, the sectors 43, including the extensions formed from the blanks 49 and ll comprise long sectors, while the sectors 43a comprise the short sectors, the intermediate spaces Q5 between the end portions of the long sectors and beyond the short-sectors 43a comprise air vent openings spaced around the apex of the canopy.

Referring again to Figs. 1 to 5, the end closure web members 48 which are disposed across the upper or inner ends of the short sectors or panels lb (Figs. 1 to 2) and 9 (Figs. 3 to 5) retard the upward escape of the air within the canopy at the ends of the shorter sectors lb (or 9) provid ing better inflation for the short sectors and the guide surface portions.

While I have illustrated several modified forms of canopy construction for carrying my invention into effect it is to be understood that I do not wish to be limited to the precise details of construction as set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

What I claim is:

1. A parachute comprising a fabric canopy having shroud lines depending from the lower edge of the skirt thereof for connection to a load to be lowered by the canopy, said canopy comprising a plurality of load carrying radial gores secured together along their adjacent edges, comprising predetermined gores of substantially equal length, and intermediate gores having a materially different length, the angular relation between the opposite side edges of all of the gores of the canopy being substantia ly identical, forming a canopy having long and short gores alternately arranged around its center to provide spaced air vent openings in the canopy between the longer gores intermediate the bottom edge and the center of the canopy.

2. In a parachute, a canopy comprising a plurality of alternate long and short load carrying gores secured together along their adjacent edges to form an annular skirt portion the angular relation between the opposite side edges of all of the gores being similar, shroud lines extending downwardly and inwardly from the pcriphery of the skirt portion for connection to a load to be lowered by the canopy with the opposite edges of the gores secured to said shroud lines, providing a canopy having a plurality of circumferentially spaced, elongated, radially disposed vent openings formed therein located between its center and periphery.

3. In a parachute, a fabric canopy of substantially hemispherical shape during descent, formed of a plurality of radially disposed load carrying fabric gores having segmental shapes with substantially identical angular relation between their opposite side edges secured together along their adjacent edges, a shroud line secured to the canopy along the adjoining edges of each pair of the gores and depending downwardly from the periphery of the canopy for connection with a load to be suspended and lowered by the canopy, said canopy comprising alternate full length fabric gores extending between the shroud lines from the periphery to the center of the canopy, and intermediate fabric gores of materially shorter length extending between the shroud lines and said full length gores to form a canopy having radially disposed vent openings therein located between the center of the canopy and its periphery and between the full length gores.

4. In a fabric parachute having low opening shock, high drag, positive opening characteristics and inherent stability, a canopy having a hemispherical shape during descent, comprising a skirt portion composed of a plurality of short and long load carrying gores of substantially similar maximum widths, tapering equally from the periphery of the canopy toward the center of the canopy, secured together along their adjacent edges to form circumferentially spaced radially disposed air vent openings about the center of the canopy, located between the skirt portion and the center of the canopy at the ends of the short load carrying gores.

5. In a fabric parachute, a circular canopy comprising a plurality of radially disposed load carrying fabric gores having a segmental shape secured together along their adjacent edges, intermediate gores thereof having a similar segmental shape to the aforementioned gores having cut away portions forming spaced air vent Openings during descent extending through the canopy causing turbulence and interference in the air passing therethrough during the descent of the canopy.

6. In a parachute, a canopy having a periphery, shroud lines extending downwardly and inwardly at substantially equally spaced points around the periphery, said canopy comprising load carrying long gores of segmental shape extending from the periphery to substantially the center of the canopy, and intermediate short gores having a similar segmental shape to the aforementioned segmental gores terminating intermediate the periphery and the center of the canopy to provide air venting openings beyond the ends of the short gores during descent disposed radially around the center of the canopy.

'7. Apparatus as claimed in claim 6, in which the longer sectors extend downwardly beyond the shorter sectors to provide a plurality of vent openings extending through the canopy between adjacent pairs of the shroud lines and below the short sectors.

8. In a parachute, a canopy, formed of substantially similar shaped radial sectors of unequal length disposed alternately around a common center and secured together along their adjacent edges to form alternate long and short similar shaped radial sectors with the ends of the longer sectors extending beyond the ends of the shorter sectors, to form spaced air vent openings around the center of the canopy at the ends of the short sectors and between the ends of adjacent long sectors.

9. In a parachute, a canopy of the sheet material comprising a plurality of radial segments with the angular relation between the radial edges of all segments substantially similar having alternate long and short radial dimensions from the center of the canopy sheet, secured together along their adjacent edges providing air vent openings located around the periphery of the canopy between the ends of adjacent long segments, and shroud lines extending downwardly along the edges of the vent openings and secured to the edges of the long segments, said shroud lines converging downwardly and adapted to have a load to be lowered by the canopy secured thereto.

10. A parachute having a canopy composed of a plurality of segmental gores extending radially outward from the canopy center to the skirt portion, and secured together along their adjacent edges, alternate gores each having portions cut away to form equally spaced air vent openings disposed around the center of the canopy extending through the canopy between the center and the skirt portion, the angular relation between the opposite radial edges of all segments being similar, and shroud lines connected to the skirt portion at the adjacent edges of the gores and the edges of the cut away portions.

11. In a parachute, a canopy comprising a plurality of radial full length and truncated segments secured together along their adjacent edges to form a plurality of circumierentially spaced segmental openings through the canopy, the angular relation between the opposite radial edges of all of the segments being similar. extending radially from the center of the canopy.

12. In a parachute, a hemispherical canopy comprising a plurality of radially disposed segmental long and short gores in which the angular relation between the opposite radial edges of all gores are similar, said gores extending from the center of the canopy to the skirt portion, shroud lines connected to the canopy skirt portion along the adjacent edges of the gores and extending downwardly and inwardly for connection to a load to be lowered by the canopy, said canopy having vent openings formed therein located between alternate pairs of the shroud lines, and between the ends of the alternate long gores.

13. Apparatus as claimed in claim 12 including closure web members secured across the ends of the short gores substantially transversely to the direction of the outer end portion of the long gores.

14. In a parachute, a canopy having a skirt portion, comprising a plurality of radially disposed load carrying segmental panels of similar segmental shape and size connected together along their adjacent edges, shroud lines extending across the canopy along the connected edges of the panels and then straight downwardly and inwardly from the skirt portion for connection to a load to be lowered by the canopy, and equally spaced flexible air deflecting means disposed at the outer ends of alternate panels forming flexible extremities at the outer ends of the alternate panels and extending throughout their length across the space between predetermined adjacent pairs of the shroud lines connecting said alternate panels, each secured at their opposite sides to the shroud lines, to provide downwardly tapering air vent openings equally spaced around the skirt portion of the canopy, below its periphery.

15. In a parachute, a canopy comprising a plurality of elongated radial adjoining load carrying sectors secured together along their adjoining edges, shroud lines extending from the top of the canopy, secured thereto along said adjoining edges and converging downwardly and inwardly toward each other from the periphery of the canopy, adapted to be secured to a load suspended from and to be lowered by the parachute, said radial sectors being alternately long and short relative to each other with the angular relation between the opposite radial edges of all sectors similar to form venting openings through the canopy between the long sectors, at the ends of the short sectors.

16. In a parachute, a canopy comprising a plurality of adjoining similar angularly shaped radial segments secured together along their adjoining edges, individual shroud lines connected to the canopy along said adjoining edges, adapted to extend straight to a load to be suspended below and lowered by the parachute, fabric extensions formed on the outer ends of spaced pairs of the segments having each of their opposite side edges secured to a pair of adjacent spaced straight shroud lines extending from the opposite edges of the last mentioned segments, forming a canopy comprising a plurality of relatively spaced long radial segments with shorter radial segments disposed therebetween to provide a plurality of venting openings located around the periphery of the canopy, one venting opening extending between each of the said extensions, each extension having an area between its connected shroud line at least equal to the area of the opening between the two adjacent extensions connected to the same shroud lines.

17. In a parachute, a fabric canopy comprising a plurality of radially disposed adjoining load carrying gores secured together along their adjoining edges to form an annular canopy sheet, shroud lines secured to the canopy along the secured edges of the gores and extending straight downwardly and inwardly below and toward the descent axis of the canopy when the canopy is inflated, adapted to be secured to a load to be suspended and lowered by the parachute, and flexible extension members secured to the outer ends of predetermined circumferentially spaced gores with their opposite side edges secured. to shroud lines which extend from the opposite sides of the said predetermined gores, to increase the length of those gores and provide air venting openings therebetween having an area not greater than the area, of one of the adjacent extensions.

18. An extension member for parachute canopies of the fiat sheet type comprising a plurality of fabric gores extending radially from the apex of the canopy to its periphery, having adjoining opposite edges secured together to form an annular sheet and shroud lines extending downwardly and inwardly from adjoining edges of the gores adapted to have a load to be lowered by the parachute secured ther to, said extension comprising a flat fabric sheet having a length materially greater than the width between two adjacent shroud lines at the periphery of the canopy, whereby said extension may be secured at its side edges to the shroud lines and will bag outwardly, to form a substantially semi-cylindrical extension below the gore when its upper end is secured to the outer end of the gore, and a fabric insert member inclining from the outer end of the semi-cylindrical portion upwardly toward the opposite end, secured to the semicylindrical portion to form an upwardly and outwardly inclined air deflecting guide surface portion located below the semi-cylindrical portion when the extension member is incorporated in a parachute, during the descent thereof.

19. In a, parachute, a fabric canopy comprising a plurality of radially disposed adjoining load carrying segmental gores secured together along their adjoining edges to form an annular canopy sheet, shroud lines secured to the canopy along the secured edges of the gores and extending downwardly and inwardly below and toward the descent axis of the canopy, adapted to be secured to a load to be suspended and lowered by the parachute, and flexible extension members secured to the outer ends of predetermined circumferentially spaced gores with their opposite side edges secured to the shroud lines which extend from the opposite sides of the said predetermined gores to increase the length of these gores and provide air venting openings therebetween, said extension members being adapted to be secured to the ends of predetermined gores of a conventional circular parachute canopy, each comprising a flexible substantially semi-circular fabric portion having opposite side edges adapted to be secured to the adjacent shroud lines extending from the opposite sides of the predetermined gores, and a flexible flat fabric portion inclining upwardly from the lower edge of the semi-circular portion, the upper end of each of said sen1icylindrica1 portions being adapted to be secured to the lower end of each of said predetermined gores of the conventional parachute with the flat portion forming an upwardly and outwardly inclined air deflecting guide surface extending downwardly from the semi-cylindrical surface of the extension, forming guide surface portions for the conventional circular parachute for increasing the stability of the parachute during descent, with the air venting openings therebetween located in spaced relation to each other around the skirt portion of the conventional canopy below the lower edge thereof and the extensions retarding initial filling or the parachute during initial opening thereof.

20. In a parachute, a substantially circular canopy comprising a plurality of tapered gore members connected together along their tapered edges to form the canopy, shroud lines connected to the canopy at said connected tapered edges and extending therefrom substantially straight downwardly and inwardly toward the descent axis of the canopy for connection to, and suspension of, a load to be suspended and lowered by the canopy, a guide surface extension member connected to the outer end of at least one of said gore members comprising a fabric member having a substantially truncated triangular perimeter, comprising an upper edge substantially equal in length to the width of the connected gore member at its outer end, opposite side edges converging straight downwardly and inwardly toward said descent axis from the opposite ends of said upper edge and connected along said opposite side edges to the downwardly and inwardly extending shroud lines at the opposite sides of the said connected gore memher, and a bottom edge having a length between the lower ends of said side edges substantially equal to the space between the connected shroud lines at said opposite side edges, disposed in spaced substantially parallel relation to the lower edge of the canopy at the outer end of the connected gore member.

21. In a parachute having a descent axis, an annular supporting canopy having an apex and a periphery comprising a plurality of tapered gore members radiating outwardly from said apex to said periphery, connected together along their tapered side edges, a plurality of shroud lines connected to the canopy at the outer ends of said connected tapered side edges and converging inwardly and downwardly therefrom toward the said descent axis for connection to a load to be suspended and lowered by the canopy, a plurality of fabric panel extension members spaced around said periphery and comiected thereto at the outer ends of predetermined gore members between the shroud lines at the opposite sides of said predetermined gore members, said fabric panel extensions being shaped to provide truncated triangular perimeters, having upper edges substantially equal in length to the length of the outer ends of the predetermined gore members which are connected thereto, and shaped to provide opposite side edges converging downwardly and inwardly toward the descent axis of the canopy from the opposite ends of said upper edges substantially parallel to the downwardly and inwardly converging shroud lines from the opposite sides of the said predetermined gore members and connected throughout their lengths to said last mentioned shroud lines, each of said extensions being shaped to provide a lower edge disposed in downwardly spaced relation below the periphery of the canopy, substantially parallel to said periphery, said lower edges having lengths substantially equal to the distance between the last mentioned shroud lines at opposite sides of said predetermined gore members, at the lower ends of the downwardly and inwardly converging side edges of said extensions.

22. In a parachute having a circular canopy having an apex, a peripheral skirt portion, and a descent axis, shroud lines connected at spaced points around the peripheral skirt portion, converging downwardly therefrom toward the descent axis of the canopy for connection to a load to be suspended and lowered by the canopy, and truncated triangular fabric extensions interposed between predetermined spaced shroud lines having 1' 361 edges connected to the said periphery itermediate said predetermined spaced shroud and opposite side edges inclining downwardly inwardly from the opposite ends of said upper edges toward said descent axis and connected throughout their lengths to the shroud lines at the opposite sides of said extensions, each extension having a lower edge disposed in downwardly spaced substantially parallel rela tion to said peripheral skirt portion, below its upper connected edge.

23. In a parachute having a descent axis, an annular canopy having an apex and a peripheral skirt portion, a plurality of shroud lines connected to the canopy at a predetermined spaced point around said peripheral skirt portion, converging downwardly and inwardly therefrom toward said descent axis, for connection at their lower ends to aload to be suspended and lowered by the canopy, a plurality of fabric extension members spaced around the said peripheral skirt portion between predetermined spaced shroud lines connected at their upper edges to ca shirt portion and shaped to provide a substantially trapezoidal perimeter having opposite side edges converging downwardly and inwardly toward said descent axis in juxtaposed parallel relation to said spaced predetermined shroud lines and connected at their lower ends clining downwardly and outwardly from said peripheral skirt portion between the said spaced predetermined shroud lines and connected at its opposite side edges to said predetermined spaced shroud lines and having a lower edge shaped to provide a guide surface panel receiving recess at the lower end of said outwardly curved surface extending between the last mentioned predetermined shroud lines substantially in a plane inclining upwardly and outwardly, relative to said descent axis, from the lower ends of the side edges of said upper curved fabric member to a point on the curved surface thereof intermediate said side edges, said lower guide surface panel member being shaped to provide an upper substantially semi-eliiptically curved edge, equal in length to the edge of the guide surface panel receiving recess and secured to the upper curved fabric member around the edge of said recess, said guide surface pan l member having a bottom edge extending between the opposite lower ends of the said opposite side edge of the upper curved fabric member substantially equal in length to the distance between the connected predetermined spaced shroud lines at the lower ends of the said opposite side edges of said upper curved fabric 14 member, constituting a plurality of upwardly and outwardly inclined guide surface members of semi-elliptical shape spaced around and below the periphery of the canopy at the lower ends of the outwardly and downwardly inclined curved surfaces of the upper fabric members.

25. A parachute canopy having a plurality of air deflecting elements each of which is spaced circumferentially from adjacent air deflecting elements on opposite sides thereof, and extending downwardly below the peripheral edge of the canopy so as to provide alternate air deflecting and air venting zones about the skirt of the canopy for increasing the turbulence of air flowing outward from beneath the canopy during a parachutev descent, suspension lines connected to the canopy and extending downwardly individually and in spaced relation from spaced points at the peripheral edge of the canopy to a load supporting point, each of said air deflecting elements having a substantial lateral width at its lower edge and being fixedly attached at its opposite lower corners to two of said spaced suspension lines so that the lower edge of the air deflecting elements will be held extended by the suspension lines at all times when the parachute is in use.

26. A parachute canopy of the character defined in claim 25, wherein the air-deflecting elements have their opposite sides approximately parallel near their lower edge.

27. A parachute canopy of the character defined in claim 25, wherein each air deflecting element includes a surface extending downwardly and inwardly to the lower edge of the element so as to increase the stability of the parachute.

28. A parachute canopy of the character defined in claim 25, wherein the canopy embodies a plurality of generally triangular sectors secured together along their radially adjacent edges with suspension lines extending along said edges downward and then inward from the peripheral edge of the canopy to a load supporting point, at least a part of each air deflecting element extending downwardly and inwardly between two of said spaced suspension lines below the peripheral edge of the canopy.

29. A parachute canopy of the character defined in claim 25, wherein the canopy embodies radially disposed adjoining load carrying gores secured together along their adjoining edges to form an annular canopy and the air deflecting elements are formed of flexible fabric portions secured to the outer ends of predetermined circumferentially spaced gores with the opposite side edges of each air deflecting element being secured to the suspension lines which extend from the opposite sides of the corresponding gore so as to increase the length of said gore and to provide relatively unobstructed air venting openings between adjacent air deflecting elements.

30. A parachute canopy of the character defined in claim 25, wherein the air deflecting elements each comprise a loose, air pocketing member having a downwardly and outwardly extending upper portion and a downwardly and inwardly extending lower portion so that when the parachute is in use said elements combine to present a plurality of circumferentially spaced out wardly projecting air-retarding v pockets separated by intermediate, relatively unobstructed air venting zones.

31. A parachute canopy of the character defined in claim 25, wherein each air deflecting element consists of a pocket-like substantially trapezoidal. outwardly curving fabric portion having its upper edge secured to the lower edge of the canopy and its two side edges secured to two adjacent suspension lines and a plane fabric portion having at its lower edge a width corresponding to the distance between said two adjacent suspension lines and being secured at its lower corners to said two suspension lines respectively, said plane fabric portion having an elliptlcally rounded upper edge connected to the correspondingly rounded lower edge of the outwardly curving trapezoidal fabric portion.

References Cited in the file of this patent UNITED STATES PATENTS Number 10 Number Name Date Driggs Mar. 20, 1934 Tricau Aug. 3, 1937 Hart June 7, 1938 Manson Apr. 23, 1946 Volf July 23, 1946 Kowalski July 31, 1951 FOREIGN PATENTS Country Date Italy Oct. 10, 1947 Great Britain Mar. 13, 1940 France July 3, 1912 France Feb. 14, 1923 

